Blended contact fingers for preventing cracks during thin substrate handling

ABSTRACT

A contact for providing a connection to a substrate in a substrate plating system includes a body having an arcuate shape. The arcuate shape of the body is configured to conform to a shape of at least a portion of a substrate arranged on a lip seal and a cup of the substrate plating system. A plurality of first contact fingers extend a first distance from the body. A plurality of second contact fingers extend a second distance from the body. The first distance is greater than the second distance.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.63/018,039, filed on Apr. 30, 2020. The entire disclosure of theapplication referenced above is incorporated herein by reference.

FIELD

The present disclosure relates to electroplating systems and moreparticularly to blended contact fingers for electroplating systems.

BACKGROUND

The background description provided here is for the purpose of generallypresenting the context of the disclosure. Work of the presently namedinventors, to the extent it is described in this background section, aswell as aspects of the description that may not otherwise qualify asprior art at the time of filing, are neither expressly nor impliedlyadmitted as prior art against the present disclosure.

In some applications, a substrate such as a semiconductor wafer isthinned using a grinding wheel to a desired thickness prior todownstream processing. The substrate may be too thin to sufficientlysupport the substrate during grinding, subsequent handling and/ordownstream processing. In this situation, the substrate is bonded to acarrier substrate, which acts as a support structure, and later detachedfrom the carrier substrate when processing is complete. Even with theadditional support provided by the carrier substrate, the substrate isprone to cracking and chipping during downstream processing.

SUMMARY

A contact for providing a connection to a substrate in a substrateplating system includes a body having an arcuate shape. The arcuateshape of the body is configured to conform to a shape of at least aportion of a substrate arranged on a lip seal and a cup of the substrateplating system. A plurality of first contact fingers extend a firstdistance from the body. A plurality of second contact fingers extend asecond distance from the body. The first distance is greater than thesecond distance.

In other features, the plurality of first contact fingers are configuredto contact a seed layer arranged above a substrate bonded to a carriersubstrate during plating. The plurality of second contact fingers areconfigured to contact the carrier substrate at a location outward from aradially outer edge of the substrate during plating. Ones of theplurality of first contact fingers alternate with ones of the pluralityof second contact fingers. P of the plurality of first contact fingersare arranged immediate adjacent to one another and Q of the plurality ofsecond contact fingers are arranged immediately adjacent to one another.P and Q are integers greater than or equal to 1. P and Q are equal,greater than one and less than twenty. P is greater than Q. Q is greaterthan P.

In other features, a plurality of third contact fingers extend a thirddistance that is different than the first distance and the seconddistance. A plurality of “U”-shaped cutouts are located between theplurality of first contact fingers and the plurality of second contactfingers. The plurality of first contact fingers are connected togetherat radially outer ends thereof.

In other features, radially inner ends of at least one of the pluralityof first contact fingers has a “V”-shaped profile. The first distance isin a range from 0.6 mm to 4.2 mm and the second distance is in a rangefrom 0.2 mm to 1.0 mm. The first contact fingers have a thickness in arange from 0.001″ to 0.0045″ and the second contact fingers have athickness in a range from 0.0035″ to 0.007″. The body of the contact isannular.

In other features, the contact includes N ones of the body, each of theN ones spans 360°/N, and the N ones are arranged in a contiguous manneraround a periphery of the lip seal. A plating system includes thecontact, a cup, and a lip seal arranged on the cup. The contact isarranged between the lip seal and the substrate during plating.

A contact configured to rest on a lip seal of a cup includes a firstbody having an arcuate shape and including a plurality of first contactfingers extending a first distance from the first body and a pluralityof first spaces located between selected ones of the plurality of firstcontact fingers. A second body has an arcuate shape and includes aplurality of second contact fingers extending a second distance from thesecond body and a plurality of second spaces located between selectedones of the plurality of first contact fingers. The second distance isgreater than the first distance. The first body and the second body areconfigured to overlap with the plurality of first contact fingersaligned with the plurality of second spaces and with the plurality ofsecond contact fingers aligned with the plurality of first spaces.

In other features, the plurality of second contact fingers areconfigured to contact a seed layer of a substrate bonded to a carriersubstrate. The plurality of first contact fingers are configured tocontact the carrier substrate radially outwardly from the substrate. Theplurality of first contact fingers are configured to contact a seedlayer outwardly from a radially outer edge of the substrate.

A plating system includes the contact, a cup and a lip seal arranged onthe cup.

A contact providing an electrical connection to a substrate in asubstrate plating system comprises a first body and a second body. Thefirst body has an arcuate shape and includes N first contact fingersextending a first distance from the first body, where N is an integergreater than 1. The second body has an arcuate shape and includes Msecond contact fingers extending a second distance from the second body,where M is an integer greater than 1, and a ratio of N:M is 1:P, where Pis a positive integer. The second distance is greater than the firstdistance. The N first contact fingers and the M second contact fingershave the same width. The first body and the second body are configuredto overlap, with the N first contact fingers aligned with and stacked ontop of at least a plurality of the M second contact fingers.

In another feature, P=1, P=2, or P=3.

In another feature, the M second contact fingers are configured tocontact a seed layer of a substrate bonded to a carrier substrate.

In another feature, the N first contact fingers are configured tocontact the carrier substrate radially outwardly from the substrate.

In another feature, the N first contact fingers are configured tocontact a seed layer outwardly from a radially outer edge of thesubstrate.

Further areas of applicability of the present disclosure will becomeapparent from the detailed description, the claims and the drawings. Thedetailed description and specific examples are intended for purposes ofillustration only and are not intended to limit the scope of thedisclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure will become more fully understood from thedetailed description and the accompanying drawings, wherein:

FIGS. 1A to 1F illustrate a method for attaching a substrate to acarrier substrate;

FIGS. 2A to 2D illustrate problems that may arise when attaching thesubstrate to the carrier substrate;

FIG. 3 is a side cross-sectional view of a substrate holder used duringplating of the substrate;

FIGS. 4A and 4B are enlarged views illustrating contact fingers duringplating;

FIGS. 5A and 5B are plan views illustrating a contact including anarcurate body and contact fingers;

FIG. 5C is a plan view illustrating an example of a contact includingblended contact fingers according to the present disclosure;

FIG. 5D is a side view illustrating the blended contact fingers incontact with the substrate;

FIGS. 6A to 6E are plan views illustrating other examples of contactsincluding blended contact fingers according to the present disclosure;

FIGS. 7A to 7C are plan views illustrating other examples of overlappingcontacts including blended contact fingers according to the presentdisclosure;

FIG. 7D is a side view illustrating overlapping contacts includingblended contact fingers in contact with the substrate;

FIGS. 8A to 8D are side views illustrating variations of the blendedcontact finger profiles according to the present disclosure;

FIGS. 9A to 9C illustrate width variations for the blended contactfingers;

FIGS. 10A and 10B illustrates a contact finger with a “V”-shaped endprofile on a radially-inner end of the blended contact finger accordingto the present disclosure;

FIGS. 11A to 11C are side views illustrating the effect of differentblended contact finger profiles on spring force against the substratesurface;

FIGS. 12A to 12C illustrate various types of contacts according to thepresent disclosure;

FIGS. 13A to 13C are plan views illustrating other examples ofoverlapping contacts including blended contact fingers according to thepresent disclosure;

FIGS. 14A to 14C are plan views illustrating other examples ofoverlapping contacts including blended contact fingers according to thepresent disclosure; and

FIG. 15 is a side view illustrating overlapping contacts of FIGS.13A-14C including stacked contact fingers in contact with the substrate.

In the drawings, reference numbers may be reused to identify similarand/or identical elements.

DETAILED DESCRIPTION

The present disclosure relates to contacts used during substrateprocessing such as plating. The contacts according to the presentdisclosure include blended contact fingers. A first group of the blendedcontact fingers is designed to contact a radially outer edge of thesubstrate bonded to the carrier substrate. The first group of contactfingers provides electrical connections to a seed layer on the substrateduring plating. A second group of the blended contact fingers isdesigned to contact the carrier substrate radially outside of thesubstrate. The second group of contact fingers help break a seal formedby a lip seal to the substrate.

Referring now to FIGS. 1A to 1F, a method for attachment of a substrate14 such as an active Si wafer to a carrier substrate 10 is shown. InFIG. 1A, an adhesive layer 12 is applied to a first surface on one sideof a carrier substrate 10. In FIG. 1B, a first surface of the substrate14 is arranged in contact with the adhesive layer 12. In FIG. 1C, thesecond surface of the substrate 14 is ground by a grinding wheel toreduce a thickness of the substrate 18 to a desired thickness.

In FIG. 1D, a thinned substrate 18 is supported by the carrier substrate10 during and after grinding to prevent damage during handling or otherdownstream processing. In FIG. 1E, the handling and/or other downstreamprocessing such as deposition, etching, patterning, plating and/or othersubstrate treatments are performed (generally on the side of thesubstrate that was ground). In FIG. 1E, the substrate 18 is eventuallyseparated from the carrier substrate 10 to produce a thinned andprocessed substrate.

Referring now to FIGS. 2A to 2D, several problems may arise whenattaching the substrate 14 to the carrier substrate. In the example inFIG. 2A, a bonded substrate assembly 200 includes the carrier substrate10 and other layers 204 including the adhesive layer 12, a substrate 210and a seed layer 214. In some examples, the seed layer 214 is a copper(Cu) seed layer. In some examples, the carrier substrate 10 is made ofglass or silicon and has a thickness in a range from 400-700 μm,although other thicknesses can be used. In some examples, the thicknessof the substrate 18 after grinding is in a range from 10 to 150 μm,although other thicknesses can be used.

In FIG. 2B, the seed layer 214 may also cover a portion of the carriersubstrate as shown at 230. In FIG. 2C, the adhesive layer 12 may notextend fully under the substrate 210, which may make the substrate proneto cracking or breaking. In FIG. 2D, the adhesive layer 12 may alsoextend beyond the substrate 210 as shown at 250.

Referring now to FIG. 3 , a plating assembly 300 includes a cup 312 anda cone 314. While a specific assembly is shown for discussion purposes,other types of assemblies, handling equipment or processing equipmentcan be used. The cup 312 is supported by a top plate 310 and struts 316.Generally, a bonded substrate 320 rests on the cup 312 which providessupport. The cup 312 includes an opening through which electrolyte froma plating cell contacts the substrate 320. The substrate 320 has afront/working side 322 where plating occurs. An outer periphery ofsubstrate 320 rests on a lip seal 330 of the cup 312. A spindle 334causes the cone 314 to press against a cone seal 336 to hold thesubstrate 320 in place and to seal the substrate 320 against the lipseal 330. A contact ring 350 including contact fingers is locatedbetween an upwardly facing surface of the lip seal 330 and a downwardlyfacing surface of of the substrate 320. The contact ring 350 provides anelectrical connection to the substrate 320 during plating.

Referring now to FIGS. 4A and 4B, contact fingers of a contact are shownduring plating or other substrate treatment. In FIG. 4A, a contactfinger 414 rests on a lip seal 412 supported by a cup (not shown). Aradially inner end 416 of the contact finger 414 acts as a spring as abonded substrate 418 is compressed against the lip seal 412. In FIG. 4B,pressure from the radially inner end 416 of the contact finger 414against the substrate 210 may cause the substrate 210 to crack and/orone or more layers may break away as shown at 204-1.

The contact fingers serve as an electrical connection from a powersupply to the substrate. Some of the contact fingers need to make goodelectrical contact with the seed layer 214 on the substrate 210.Generally, longer, flatter contact fingers make better electricalcontact. Contacts also serve a secondary purpose by providing lift onthe substrate after plating to free the substrate from suction againstthe lip seal 414. Steep angle contacts with more spring force providebetter lift, whereas flatter contacts are more prone to sticking to thelip seal 412. Contact fingers (particularly those that provide stronglift) are a key source of wafer cracking/chipping on thin substratessuch as active Si wafers.

Systems and methods discussed herein to provide a contact design thatmakes good electrical contact with the seed layer on the substrate,provides strong lift to prevent wafer sticking to the lip seal afterplating, and does not crack or chip the substrate. The presentdisclosure relates to contacts including blended contact fingers and/orother features addressing the foregoing problems. In some examples, theblended contact fingers include two or more types of contact fingersthat are used to contact a single substrate.

Referring now to FIGS. 5A and 5B, a contact 500 including a plurality ofcontact fingers is shown. In FIG. 5A, the contact 500 includes an outerportion 510 and an inner portion 514 extending radially inwardly fromthe outer portion 510. The inner portion 514 includes contact fingersprojecting radially inwardly (examples shown in FIGS. 5B, 5C and 6A to6E). While the inner portion 514 of the contact 500 includes the contactfingers, the contact fingers can be arranged on the outer portion 510.In FIG. 5B, the contact fingers 530 extend radially inwardly by the samedistance.

In FIGS. 5C and 5D, the contact fingers have different lengths and areblended. First contact fingers 540 extend inwardly more than secondcontact fingers 550. In some examples, the first contact fingers 540alternate with the second contact fingers 550. However, differentpatterns may be used. For example, F of the first contact fingers 540can be arranged between G of the second contact fingers, where F and Gare integers greater than or equal to one.

This blended contact finger arrangement has several advantages. Thesecond contact fingers 550 make physical contact with the carriersubstrate and typically not with the substrate, which minimizes risk ofcracking/chipping. The second contact fingers 550 provide lift toprevent the substrate from sticking to the lip seal.

In some examples, the second contact fingers 550 have a length in arange from 0.2 mm to 1.0 mm (e.g. 0.4 mm). In some examples, the secondcontact fingers 550 have steeper angle than the first contact fingers540. In some examples, the angle of a second bend of the second contactfingers 550 closest to the substrate is in a range from 45° to 135°(e.g. 105°).

In some examples, the second contact fingers 550 are stiffer than thefirst contact fingers 540. For example, the second contact fingers mayuse a material having a thickness in a range from 0.0035″ to 0.007″(e.g. 0.004″). In some examples, the second contact fingers 550 can alsomake electrical contact with the seed layer if the seed layer extendsbeyond the substrate as shown in FIG. 2B.

The first contact fingers 540 make electrical contact with thesubstrate. Characteristics include longer length for good electricalcontact. In some examples the length is in a range from 0.6 mm to 4.2 mm(e.g. 1.3 mm). In some examples, the second bends of the first contactfingers 540 have a shallower angle in a range from 45° to 135° (e.g.115°). In some examples, the first contact fingers 540 are made of athinner material than the second contact fingers 550. In some examples,the thickness of the first contact fingers 540 is in a range from 0.001″to 0.0045″ (e.g. 0.002″) to reduce thin wafer cracking and chipping

In some examples, the first contact fingers 540 and the second contactfingers 550 are made of a conductive material. For example, theconductive material may include stainless steel (SS), platinum coatedSS, Paliney® 7, beryllium copper, and/or other alloys or metals.

The blended contact fingers described herein enable shallower, gentlerelectrical contact (using longer length contact fingers) to minimizecracking risk, while reducing sticking risk (using shorter contactfingers) as shown in FIG. 5D.

Referring now to FIGS. 6A to 6E, other examples of contacts includingblended contact fingers are shown. In FIG. 6A, the contact 600 is shownto include an outer portion 606 and an inner portion 602 includingcontact fingers 610, 614 and 620 having increasing lengths,respectively. Instead of alternating between two types of contacts, thecontact 500 includes 3 or more radial lengths, circumferential widths,material thicknesses and/or material types.

In FIGS. 6B, 6D and 6E, the contact ring portion 630 is shown to includean outer portion 606 and an inner portion 608 including a group of Pcontact fingers 634 having the same first length arranged adjacent toone another. The contact ring portion 630 includes a group of Q contactfingers 638 having the same second length arranged adjacent to oneanother where the first length is shorter than the second length. Thegroup of P contact fingers 634 is arranged adjacent to the group of Qcontact fingers 638. P and Q are integers greater than or equal to 1where at least one of P or Q is greater than or equal to 1. In someexamples, P and Q are less than or equal to 30, 20, 10, 8, 6 or 4. Insome examples, P and Q are equal. In FIG. 6B, P=Q=6 for the contact ringportion 630. In FIG. 6D, P=1 and Q=2 for a contract ring finger 670. InFIG. 6E, P=1 and Q=3 for a contract ring finger 680. While specificexamples are shown, other combinations are contemplated.

In FIG. 6C, a contact ring portion 640 includes “U”-shaped cutouts 652defining first contact fingers 650 and second contact fingers 654. Twoor more of the second contact fingers 654 are connected together andextend further than the first contact fingers 650. In some examples,two, three, four or more of the second contact fingers 654 are joinedtogether to make a circumferentially longer contact, which maximizescontact area on the seed layer. In some examples, additional cutouts(not shown) may be made between selected ones of the second contactfingers 654 to separate the second contact fingers 654 to a desirednumber of connected second contact fingers 654. In other examples, allof the second contact fingers 654 remain joined together. This designmay be beneficial for thin seed layers and/or marginally distributedseed layers.

Referring now to FIGS. 7A to 7D, overlapping contacts including blendedcontact fingers are shown. In FIG. 7A, a first contact 710 includes anouter portion 712 and an inner portion 714. Contact fingers 716 extendinwardly and are separated by spaces 718. A second contact 720 includesan outer portion 712 and an inner portion 714. Contact fingers 724extend radially inwardly and are separated by spaces 728. The contact710 is arranged in an overlapping manner on the second contact 720 withthe contact fingers 716 aligned with spaces 728 and with the contactfingers 724 aligned with the spaces 718 as can be seen in FIG. 7C. Theoverlapping contacts can remain independent pieces that lay on top ofone another and are held in place when assembled into the cup.Alternatively the overlapping pieces can be spot-welded, glued, orpermanently attached to one another using other approaches.

In FIG. 7D, the contact fingers 724 provide electrical contact to theseed layer and the contact fingers 716 contact the carrier substrate tohelp break the seal after plating. FIGS. 7A to 7C show one of thecontact fingers 716 from the first contact 710 between each of thecontact fingers 724 from the second contact 720. Other patterns mayinclude groups of C contact fingers on the first contact ring arrangedimmediately adjacent to one another and separated by other groups byspaces and a group of D contact fingers on the second contact ringarranged immediately adjacent to one another and separated by spaces,where C and D are integers greater than one. In some examples, C=D. Inother examples, C<>D and the widths are varied. For example, C=2 and D=1with the width of the D contact fingers being twice the width of the Ccontact fingers.

Referring now to FIGS. 8A to 8D variations of the blended contact fingerprofiles are shown. In FIG. 8A, a contact finger 810 includes a firstbend 812 in a downward direction, a second bend 814 in an upwarddirection and a radially inner end 816. In FIG. 8B, a contact finger 820includes a first bend 822 in a downward direction, a second bend 824 inan upward direction and a radially inner end 826. Edges of the contactfinger 820 are more rounded (as compared to FIG. 8A) to reduce damage tothe substrate due to digging into the substrate and/or subsequentcracking.

In FIG. 8C, the contact finger 830 includes a first bend 832 in adownward direction, a second bend 834 in an upward direction, a thirdbend 835 in a downward direction and a radially inner end 816. The thirdbend 835 provides a smoother contact surface that likewise reducesdamage to the substrate due to digging into the substrate and/orsubsequent cracking. In FIG. 8D, the contact finger 840 includes a firstbend 842 in a downward direction, a second bend 844 in an upwarddirection and a radially inner end 816. Altering the angles at the bends(particularly the first bend 842) varies the loading of the contactfinger and the pressure on the substrate.

Referring now to FIGS. 9A to 9C, a circumferential width of the blendedcontact fingers can be varied to adjust loading of the contact fingers.A wider circumferential width will have increased loading as compared toa standard circumferential width whereas a narrower width will have lessloading (assuming the same materials and thickness).

Referring now to FIGS. 10A and 10B, a profile of a radially inner end ofthe contact finger can be varied. A contact finger 1020 includes a firstbend 1022, a second bend 1024 and a radially inner end 1026. Theradially inner end 1026 has a “V”-shaped profile. Bends in the“V”-shaped profile provide increased contact pressure on the substrate.

Referring now to FIGS. 11A to 11C, the effect of different blendedcontact finger profiles and force on the substrate surface areillustrated. The location and angle of second bend on the contact fingercan have significant impact on contact force. In FIG. 11A, a cup 1110includes a bottom surface 1112 and a lip seal 1114. A contact finger1120 is supported on the lip seal 1114 and includes a first bend 1122, asecond bend 1124 and a radially inner end 1126. As can be seen, thecontact finger 1120 acts as a spring with an effective length L₁ fromthe second bend 1124 to the radially inner end 1126 of the contactfinger 1120.

In FIG. 11B, a contact finger 1140 is supported on the lip seal 1114 andincludes a first bend 1142, a second bend 1144 and a radially inner end1146. As can be seen, the contact finger 1140 acts as a spring with aneffective length L₂ from the second bend 1144 to the radially inner end1146 of the contact finger 1140. As can be seen, the effective length ofthe spring changes the impacting force on the substrate. Moreparticularly, the location and angle of the second bend on the contactfinger changes the contact force.

In FIG. 11C, a contact finger 1150 is supported on a lip seal 1152 of acup 1154. The contact finger 1150 includes a first bend 1152, a secondbend 1154 and a radially inner end 1156. When the contact finger 1150makes electrical contact with the substrate, a flatter contact/shallowerangle of the second bend 1154 reduces force on substrate and minimizeslikelihood of cracking. A flatter contact will also require lesspressure to hold the wafer in place, thereby reducing the propensity ofthe wafer to stick to the lip seal.

Referring now to FIGS. 12A to 12C, the body of the contact can be acontinuous annular ring or a group of arcuate portions combined to forman annular ring. In other examples, the contact ring can be segmentedinto A portions each spanning 360°/A, where A is an integer greater thanor equal to one. In FIG. 12B, A=2 and the contact ring portions span180°. In FIG. 12C, A=4 and the contact ring portions span 90°. In otherexamples, A=3 and the contact ring portions span 120°, A=5 and thecontact rings span 72°, etc.

Referring now to FIGS. 13A to 14C, additional configurations of contactsincluding stacked contact fingers are shown. In FIGS. 13A-13C, theshorter contact fingers 716 are fewer in number than the longer contactfingers 530, and are aligned with and stacked on top of only some of thelonger contact fingers 530. In FIGS. 14A-14C, the shorter contactfingers 716 are equal in number as the longer contact fingers 530, andare aligned with and stacked on top of the longer contact fingers 530.

In FIGS. 13A-13C, FIG. 13A is similar to FIG. 7A, and FIG. 13B issimilar to FIG. 5B. In FIG. 13A, the first contact 710 includes theouter portion 712 and the inner portion 714. The contact fingers 716extend inwardly and are separated by spaces 718. In FIG. 13B, the secondcontact 500 includes the outer portion 510 and the inner portion 514extending radially inwardly from the outer portion 510. The innerportion 514 includes the contact fingers 530 projecting radiallyinwardly. While the inner portion 514 of the second contact 500 includesthe contact fingers 530, the contact fingers 530 can be arranged on theouter portion 510. The contact fingers 716 are shorter in length thanthe contact fingers 530. The contact fingers 716 and 530 have the samewidth. The number of contact fingers 716 is less than the number ofcontact fingers 530. For example, a ratio of the number of contactfingers 716 to the number of contact fingers 530 may be 1:2, 1:3, and soon.

In FIG. 13C, the shorter contact fingers 716 are aligned with and arestacked on top of only some of the longer contact fingers 530 dependingon the 1:N ratio between the contact fingers 716 and 530, where N is aninteger greater than 1. The first contact 710 is arranged in anoverlapping manner on the second contact 500 with the contact fingers716 aligned with and stacked on top of some of the longer contactfingers 530.

In FIGS. 14A-14C, FIG. 14A differs from FIG. 13A in that a first contact711 includes the contact fingers 716 that are not separated by spaces718. Otherwise, the first contact 711 is similar the first contact 710in all other respects. FIG. 14B is the same as FIG. 13B and is thereforenot described again for brevity. The shorter contact fingers 716 areagain smaller in length than the longer contact fingers 530. The contactfingers 716 and 530 again have the same width. However, the number ofcontact fingers 716 is equal to the number of contact fingers 530. Thatis, the ratio of the number of contact fingers 716 to the number ofcontact fingers 530 is 1:1.

In FIG. 14C, the shorter contact fingers 716 are aligned with and arestacked on top of the longer contact fingers 530, respectively. Thefirst contact 711 is arranged in an overlapping manner on the secondcontact 500 with the contact fingers 716 aligned with and stacked on topof the longer contact fingers 530, respectively.

FIG. 15 , which is similar to FIG. 7D, shows that the contact fingers530 provide electrical contact to the seed layer 214, and the contactfingers 716 contact the carrier substrate 418 to help break the sealafter plating. As described above with reference to FIG. 7D, theoverlapping contacts can remain independent pieces that lay on top ofone another and are held in place when assembled into the cup.Alternatively the overlapping pieces can be spot-welded, glued, orpermanently attached to one another using other approaches.

The foregoing description is merely illustrative in nature and is in noway intended to limit the disclosure, its application, or uses. Thebroad teachings of the disclosure can be implemented in a variety offorms. Therefore, while this disclosure includes particular examples,the true scope of the disclosure should not be so limited since othermodifications will become apparent upon a study of the drawings, thespecification, and the following claims. It should be understood thatone or more steps within a method may be executed in different order (orconcurrently) without altering the principles of the present disclosure.Further, although each of the embodiments is described above as havingcertain features, any one or more of those features described withrespect to any embodiment of the disclosure can be implemented in and/orcombined with features of any of the other embodiments, even if thatcombination is not explicitly described. In other words, the describedembodiments are not mutually exclusive, and permutations of one or moreembodiments with one another remain within the scope of this disclosure.

Spatial and functional relationships between elements (for example,between modules, circuit elements, semiconductor layers, etc.) aredescribed using various terms, including “connected,” “engaged,”“coupled,” “adjacent,” “next to,” “on top of,” “above,” “below,” and“disposed.” Unless explicitly described as being “direct,” when arelationship between first and second elements is described in the abovedisclosure, that relationship can be a direct relationship where noother intervening elements are present between the first and secondelements, but can also be an indirect relationship where one or moreintervening elements are present (either spatially or functionally)between the first and second elements. As used herein, the phrase atleast one of A, B, and C should be construed to mean a logical (A OR BOR C), using a non-exclusive logical OR, and should not be construed tomean “at least one of A, at least one of B, and at least one of C.”

What is claimed is:
 1. A contact providing an electrical connection to asubstrate in a substrate plating system, comprising: a body having anarcuate shape, wherein the arcuate shape of the body is configured toconform to a shape of at least a portion of a substrate arranged on alip seal and a cup of the substrate plating system; a plurality of firstcontact fingers extending a first distance from the body; and aplurality of second contact fingers extending a second distance from thebody, wherein the first distance is greater than the second distance. 2.The contact of claim 1, wherein the plurality of first contact fingersare configured to contact a seed layer arranged above a substrate bondedto a carrier substrate during plating.
 3. The contact of claim 2,wherein the plurality of second contact fingers are configured tocontact the carrier substrate at a location outward from a radiallyouter edge of the substrate during plating.
 4. The contact of claim 1,wherein ones of the plurality of first contact fingers alternate withones of the plurality of second contact fingers.
 5. The contact of claim1, wherein P of the plurality of first contact fingers are arrangedimmediate adjacent to one another and Q of the plurality of secondcontact fingers are arranged immediately adjacent to one another, whereP and Q are integers greater than or equal to
 1. 6. The contact of claim5, wherein P and Q are equal, greater than one and less than twenty. 7.The contact of claim 5, wherein P is greater than Q.
 8. The contact ofclaim 5, wherein Q is greater than P.
 9. The contact of claim 1, furthercomprising a plurality of third contact fingers extending a thirddistance that is different than the first distance and the seconddistance.
 10. The contact of claim 1, further comprising a plurality of“U”-shaped cutouts located between the plurality of first contactfingers and the plurality of second contact fingers.
 11. The contact ofclaim 10, wherein the plurality of first contact fingers are connectedtogether at radially outer ends thereof.
 12. The contact of claim 1,wherein radially inner ends of at least one of the plurality of firstcontact fingers has a “V”-shaped profile.
 13. The contact of claim 1,wherein the first distance is in a range from 0.6 mm to 4.2 mm and thesecond distance is in a range from 0.2 mm to 1.0 mm.
 14. The contact ofclaim 1, wherein the first contact fingers have a thickness in a rangefrom 0.001″ to 0.0045″ and the second contact fingers have a thicknessin a range from 0.0035″ to 0.007″.
 15. The contact of claim 1, whereinthe body of the contact is annular.
 16. The contact of claim 1, wherein:the contact includes N ones of the body, each of the N ones spans360°/N, and the N ones are arranged in a contiguous manner around aperiphery of the lip seal.
 17. A contact providing an electricalconnection to a substrate in a substrate plating system, comprising: afirst body having an arcuate shape and including: a plurality of firstcontact fingers extending a first distance from the first body; and aplurality of first spaces located between selected ones of the pluralityof first contact fingers; and a second body having an arcuate shape andincluding: a plurality of second contact fingers extending a seconddistance from the second body; and a plurality of second spaces locatedbetween selected ones of the plurality of first contact fingers, whereinthe second distance is greater than the first distance, and wherein thefirst body and the second body are configured to overlap with theplurality of first contact fingers aligned with the plurality of secondspaces and with the plurality of second contact fingers aligned with theplurality of first spaces.
 18. The contact of claim 17, wherein theplurality of second contact fingers are configured to contact a seedlayer of a substrate bonded to a carrier substrate.
 19. The contact ofclaim 18, wherein the plurality of first contact fingers are configuredto contact the carrier substrate radially outwardly from the substrate.20. The contact of claim 17, wherein the plurality of first contactfingers are configured to contact a seed layer outwardly from a radiallyouter edge of the substrate.